TWM588042U - Rotating speed switching device of electric tool - Google Patents

Abstract

A rotation speed switching device for an electric tool includes a first planetary gear mechanism and a second planetary gear mechanism which are axially connected in series. The first planetary gear mechanism has a first internal gear and a first internal gear of the first internal gear. The tooth portion meshes with a first planetary gear, and the first outer tooth portion of the first internal gear matches at least one first detent element; the second planetary gear mechanism has a second internal gear, and the second internal gear The internal tooth portion meshes with a second planetary gear, and the second external tooth portion of the second internal gear matches at least one second detent element; a knob is provided on the periphery of the first planetary gear mechanism and the second planetary gear mechanism. The knob has a detent structure. When the knob is rotated an angle in a first direction, the detent structure applies an external force to the first planetary gear mechanism to restrict the first internal gear, but the second internal gear is fixed. The planetary gear mechanism is not restricted by external force, so that the second internal gear can rotate, so that the motor gear is switched to the low speed mode. When the knob is rotated by an angle in the opposite second direction, the The moving structure applies an external force to the second planetary gear mechanism to restrict the second internal gear to be fixed, but the first planetary gear mechanism is not restricted by external force to allow the first internal gear to rotate, so that the motor gear Switched to high speed mode.

Description

Speed switching device of electric tool

The present invention relates to a rotation speed switching device of an electric tool. In particular, in addition to switching between a high rotation speed and a low rotation speed, the switching device can also expand the range between high and low rotation speeds.

The conventional electric tools used for drilling and locking work have a structure in which the power of the motor is transmitted to the output shaft via a gear system to output the power; in addition, in order to meet the actual work requirements, the final speed output through the output shaft can be switched to High or low speed.

Specifically, conventionally known electric tools that can switch between high speed and low speed generally include an output shaft for connecting to a power source, a first planetary gear mechanism axially connected to one of the output shafts, and axial movement. A second planetary gear mechanism in series with the first planetary gear mechanism, and a motor gear axially connecting the first planetary gear mechanism and the second planetary gear mechanism, and between the first planetary gear mechanism and the second planet The gear mechanism is provided with an internal gear that can be controlled to slide axially. The internal gear is connected to a push button, and the user rotates the internal gear between the first planetary gear mechanism and the second planetary gear mechanism by turning the push button. To move in the direction of direction, the internal gear matches the first planetary gear mechanism or the second planetary gear mechanism to generate different gear ratios, thereby achieving the function of switching the high speed or low speed of the output shaft.

However, since the aforementioned conventional rotation speed switching device meshes with the first planetary gear mechanism or the second planetary gear mechanism through the movement of an internal gear to generate different gear ratios, the number of teeth of the internal gear is fixed and cannot be adjusted, so The difference between the gear ratio of the internal gear after moving to the first planetary gear mechanism and the gear ratio after moving to the second planetary gear mechanism is small, and the range between low speed and high speed cannot be further expanded.

The purpose of this creation is to provide a rotation speed switching device that can expand the range between the low rotation speed and the high rotation speed of a power tool.

The rotation speed switching device of the power tool provided by this creation may include: a first planetary gear mechanism, the first planetary gear mechanism includes a plurality of first planetary gears; a second planetary gear mechanism, which is movably connected in series axially with the first planetary gear mechanism; A planetary gear mechanism, the second planetary gear mechanism includes a plurality of second planetary gears; a motor gear connected to a motor, and the motor gear axially meshes the first planetary gears and the second planetary gears And an output shaft that is axially connected to the first planetary gear mechanism; wherein when the first planetary gear mechanism is restricted by external force but the second planetary gear mechanism is not restricted by external force, the motor gear passes power through the first planetary gear mechanism The two planetary gear mechanism and the first planetary gear mechanism are transmitted to the output shaft to generate a low speed. When the second planetary gear mechanism is restricted by external force but the first planetary gear mechanism is not restricted by external force, the motor gear passes power The second planetary gear mechanism and the first planetary gear mechanism are transmitted to the output shaft to generate a high rotation speed.

The feature of this creation is that the first planetary gear mechanism further includes a first internal gear, and an inner diameter and an outer diameter of the first internal gear form a first internal tooth portion and a first external tooth portion, respectively. The tooth portion is meshed with the first planetary gears, and the first external tooth portion matches at least one first detent element; the second planetary gear mechanism further includes a second internal gear, and the inner diameter and the outer diameter of the second internal gear Forming a second internal tooth portion and a second external tooth portion, the second internal tooth portion meshing with the second planetary gears, the second external tooth portion matching at least one second detent element; and further comprising a A knob is provided on the periphery of the first planetary gear mechanism and the second planetary gear mechanism. The knob has a detent structure. When the knob is rotated by an angle in a first direction, the detent structure gives the first The planetary gear mechanism has an external force that restricts the first internal gear to be fixed, but the second planetary gear mechanism is not restricted by external force and allows the second internal gear to rotate, so that the motor gear is switched to a low speed mode, When the After the button is rotated by an angle in the opposite second direction, the actuating structure applies an external force to the second planetary gear mechanism to restrict the second internal gear to be fixed, but the first planetary gear mechanism is not restricted by external force. The first internal gear can be rotated, so that the motor gear is switched to the high-speed mode.

According to an embodiment of the present invention, the first internal tooth portion and the second internal tooth portion may have different numbers of teeth, respectively.

According to an embodiment of the present invention, it may further include a casing having an inner space, the first planetary gear mechanism and the second planetary gear mechanism are disposed in the inner space, and a side wall of the casing is along a central axis thereof. A direction segment separates a front section area and a rear section area. The side wall of the front section area is provided with a plurality of front lock holes along the circumference, and the side wall of the rear section area is provided with a plurality of rear lock holes along the circumference. The rear locking holes are staggered at an angle to each other in the circumferential direction of the housing. The first locking element is disposed in the front locking hole, and the second locking element is disposed in the rear locking hole.

According to an embodiment of the present invention, the detent structure may be a switch ring, and a side wall of the switch ring separates a front section area and a rear section area along a direction of a central axis thereof, and a plurality of side walls of the front section area are arranged along a circumference. A plurality of front slot holes, and a plurality of rear slot holes are arranged along the circumference of the side wall of the rear section area, and the front slot holes and the rear slot holes are staggered from each other in the circumferential direction of the switching ring, and the switching ring is provided in the The inner diameter of the knob. When the knob is combined with the casing, the inner diameter of the switching ring is slidably fitted to the outer diameter of the casing. When the knob is rotated an angle in the first direction, the front slot of the switching ring does not Corresponding to the position of the front locking hole, the side wall of the switching ring pushes the first detent element into the first external tooth portion to fix the first internal gear, but the rear slot hole of the switching ring corresponds to the The position of the rear locking hole allows the second detent element not to be embedded in the second external tooth portion and allows the second internal gear to rotate. When the knob is rotated an angle toward the second direction, the front of the switch ring The slot corresponds to the front lock Position so that the first detent element is not embedded in the first external tooth portion and allows the first internal gear to rotate, but the rear slot hole of the switch ring does not correspond to the position of the rear lock hole, so that the switch The side wall of the ring pushes the second detent element into the second external tooth portion to fix the second internal gear.

According to an embodiment of the present invention, the first detent element and the second detent element may be steel balls, respectively.

According to an embodiment of the present invention, the first planetary gear mechanism may include a first planetary gear plate, and the first planetary gear plate rotatably combines a plurality of the first planetary gears with a plurality of first pinion stub shafts; The second planetary gear mechanism may include a second planetary gear plate, and the second planetary gear plate is rotatably combined with a plurality of the second planetary gears by a plurality of second pinion stub shafts.

According to an embodiment of the present invention, the motor gear is preferably formed into a class shape with a first gear tooth portion and a second gear tooth portion of unequal diameters, and the first gear tooth portion meshes with the second planetary gears. And the second gear teeth mesh with the first planetary gears.

With the aforementioned technical characteristics, the present invention can design a rotation speed switching device with a larger rotation speed difference between a low rotation speed and a high rotation speed, so as to provide a wider applicability of electric tools.

The following describes the implementation of this creation in more detail with reference to the drawings and component symbols, so that those skilled in the technical field can implement it after studying this specification. Wherein, the “front” described below for different components all point to the same direction, and the “rear” is opposite to the other direction in front.

The rotation speed switching device of the electric tool provided by this creation is a device used for an electric tool (such as an electric drill) that outputs rotary power, and can be used to switch the output shaft of the electric tool to two kinds of rotation speeds, high speed and low speed.

As shown in FIG. 1 and FIG. 2, the preferred embodiment of the rotation speed switching device of the present invention includes a housing 10, a first planetary gear mechanism M1, a second planetary gear mechanism M2, a switching ring 34, and a knob. 36. An output shaft 12 and a motor gear 32. The outer shell 10 is cylindrical and has an inner space 101 formed thereon. The side wall of the outer shell 10 separates a front section and a rear section along the central axis direction. The front section is provided with a plurality of front sections along the circumference. The locking hole 102A, and the side wall of the rear region is provided with a plurality of rear locking holes 102B along the circumference. The front locking hole 102A and the rear locking hole 102B are staggered from each other in the circumferential direction of the casing 10; more specifically, For example, in FIG. 2, a virtual partition line La surrounding the circumference of the casing 10 separates a side wall of the casing 10 along a central axis direction from a front region and a rear region. The virtual partition line La does not actually exist. In addition, an external thread 103 is formed on the outer diameter of the front end of the casing 10, and the external thread 103 is used to screw together with the internal thread 381 provided on the end cap 38 to combine the end cap 38 on the front end of the casing 10. .

The first planetary gear mechanism M1 includes a first planetary gear plate 16. A plurality of first pinion stub shafts 162 are disposed at a rear end of the first planetary gear plate 16, and each first pinion stub shaft 162 is rotatably provided. The first planetary gears 18 are respectively combined; in addition, a bolt slot 161 is provided in the center of the first planetary gear plate 16, and the bolt slot 161 provides an output shaft 12 passing through the bushing 14 and a bolt groove formed in the output shaft 12. The shafts 121 cooperate with each other, so that the output shaft 12 can be driven to rotate by the first planetary gear plate 16; In addition, the first planetary gear mechanism M1 further includes a first internal gear 22, and the inner and outer diameters of the first internal gear 22 A first internal tooth portion 222 and a first external tooth portion 221 are respectively formed, and the first internal gear 22 is used to combine with the periphery of each first planetary gear 18 so that the first internal tooth portion 222 and each first planetary gear 18 Engage (as shown in Figures 3 to 5).

The second planetary gear mechanism M2 includes a second planetary gear plate 20. A plurality of second pinion stub shafts 201 are provided at the rear end of the second planetary gear plate 20, and each second pinion stub shaft 201 is rotatably The second planetary gears 26 are respectively combined; in addition, the second planetary gear mechanism M2 also includes a second internal gear 28, and the inner and outer diameters of the second internal gear 28 form a second internal tooth portion 282 and a second internal gear, respectively. External tooth portion 281, the second internal gear 28 is used to combine with the periphery of each second planetary gear 26 to cause the second internal tooth portion 282 to mesh with each second planetary gear 26 (as shown in Figs. 3, 4 and 6).示).

In actual applications, the number of teeth of the first internal tooth portion 222 of the first internal gear 22 and the second internal tooth portion 282 of the second internal gear 28 may be set differently according to the requirements of high and low speeds. The running gear ratios of the first planetary gear mechanism M1 and the second planetary gear mechanism M2 are made different, thereby expanding the range of the difference between the high speed and the low speed of the final output.

In this creation, the first planetary gear mechanism M1 and the second planetary gear mechanism M2 are axially movably combined in series in the inner space 101 of the casing 10, and a plurality of first steel balls 24 are used as first detents to be placed in each front lock. The holes 102A and the plurality of second steel balls 30 are used as the second detents to be inserted into the respective rear locking holes 102B, so that each of the first steel balls 24 can fall into the teeth of the first external tooth portion 221 of the first internal gear 22 Each second steel ball 30 may fall between the teeth of the second external tooth portion 281 of the second internal gear 28.

The motor gear 32 is a driving element for connecting to a motor (not shown in the figure). The motor gear 32 is preferably formed into a step shape with a first gear tooth portion 321 having a relatively large diameter and a relatively small diameter. A second gear tooth portion 322 of a diameter, the motor gear 32 is passed through the second planetary gear mechanism M2 and the first planetary gear mechanism M1 from the center, so that the first gear tooth portion 321 meshes with the second planetary gears 26, And the second gear teeth 322 mesh with the first planetary gears 18.

The switch ring 34 and a knob 36 together constitute an element for switching the rotation speed. The knob 36 is an operation element provided on the periphery of the first planetary gear mechanism M1 and the second planetary gear mechanism M2, and is formed as The cylindrical shape has a perforation 361, and a protruding pushing portion 362 is formed on the outer diameter surface. The switching ring 34 is provided on the inner diameter of the knob 36 as a detent structure to drive each first steel ball 24 into the first external tooth portion 221 or drive each second steel ball 30 to insert into the second external tooth portion 281; The side wall of the switching ring 34 separates a front section area and a rear section area along the center axis direction. The front section area is provided with a plurality of front slot holes 342A along the circumference, and the rear section area is provided along the circumference. A plurality of rear slot holes 342B, the front slot hole 342A and the rear slot hole 342B being staggered from each other in the circumferential direction of the switching ring 34; more specifically, for example, in FIG. A virtual partition line Lb separates the side wall of the switching ring 34 from a front section area and a rear section area along the center axis direction. The virtual partition line Lb does not actually exist.

The switch ring 34 is provided on the inner diameter of the knob 36, and then the switch ring 34 and the knob 36 are combined with the housing 10, so that the inner diameter of the switch ring 34 is slidably fitted to the outer diameter of the housing 10, and the front slot 342A and The rotation paths in the circumferential direction of the front lock hole 102A correspond to each other, and the rotation paths in the circumferential direction of the rear slot hole 342B and the rear lock hole 102B correspond to each other.

FIGS. 3 to 6 show the structure of the switching device of the present invention when it is switched to a low-speed state. When the user operates the turning portion 362 of the knob 36 to rotate an angle (turn left) in the first direction, the front of the switching ring 34 The slot hole 342A and the front lock hole 102A are staggered from each other and in a non-corresponding position, so that the side wall of the switching ring 34 pushes the first steel ball 24 into the first external tooth portion 221 of the first internal gear 22 to fix the first internal gear 22, However, the rear slot hole 342B of the switching ring 34 corresponds to the position of the rear lock hole 102B, so that the second steel ball 30 moves into the rear lock hole 102B and the rear slot hole 342B without being embedded in the second external tooth portion 282 of the second internal gear 28 Cause the second internal gear 28 to rotate. In this state, the driven motor gear 32 directly drives each second planetary gear 26 and each first planetary gear 18 to rotate, and the second planetary gear 26 drives the second internal gear 28 to rotate. However, the first internal gear 22 is fixed and does not rotate, thereby generating low-speed rotation through gear ratios preset by the first and second planetary gear mechanisms M1 and M2.

FIGS. 7 to 9 show the structure of the switching device of this creation when it is switched to a high-speed state. When the user operates the turning portion 362 of the knob 36 to rotate an angle (turn right) in the second direction, the front groove of the switching ring 34 The hole 342A and the front lock hole 102A are in positions corresponding to each other, so that the first steel ball 24 enters the front lock hole 102A and the front slot hole 342A to move without being embedded in the first external tooth portion 222 of the first internal gear 22, causing the first internal gear. 22 can rotate; but the side wall of the switching ring 34 pushes the second steel ball 30 into the second external tooth portion 281 of the second internal gear 28 to fix the second internal gear 28. In this state, the driven motor gear 32 directly Each of the second planetary gears 26 and each of the first planetary gears 18 are driven to rotate, and the first planetary gear 18 drives the first internal gear 22 to rotate but the second internal gear 28 is fixed and does not rotate, thereby passing through the first and second planetary gears. The gears M1 and M2 have a preset gear ratio to generate high-speed rotation.

Therefore, the present invention provides a wider range of speed difference between the low speed and high speed by the aforementioned switching device, so as to provide a wider applicability of electric tools.

The above are only for explaining the preferred embodiment of the creation, and are not intended to restrict the creation in any form. Therefore, any modification or change of the creation made in the same spirit of creation , Should still be included in the scope of protection of this creative intention.

10‧‧‧Shell

101‧‧‧Inner space

102A‧‧‧Front lock hole

102B‧‧‧ rear locking hole

103‧‧‧external thread

12‧‧‧ output shaft

121‧‧‧ bolt groove shaft

14‧‧‧ Bushing

16‧‧‧The first planetary gear plate

161‧‧‧ bolt slot

162‧‧‧First pinion stub shaft

18‧‧‧ the first planetary gear

20‧‧‧Second planetary gear plate

201‧‧‧ second pinion stub shaft

22‧‧‧The first internal gear

221‧‧‧ the first external tooth

222‧‧‧first internal tooth

24‧‧‧The first steel ball

26‧‧‧ Second planetary gear

28‧‧‧Second internal gear

281‧‧‧Second external tooth

282‧‧‧Second internal tooth

30‧‧‧Second Steel Ball

32‧‧‧motor gear

321‧‧‧Tooth of the first wheel

322‧‧‧Second Gear

34‧‧‧Switch ring

341‧‧‧through hole

342A‧‧‧Front slot

342B‧‧‧Back slot

36‧‧‧ knob

361‧‧‧perforation

362‧‧‧Promotion Department

38‧‧‧ end cap

381‧‧‧internal thread

La, Lb‧‧‧ virtual divider

M1‧‧‧First planetary gear mechanism

M2‧‧‧Second planetary gear mechanism

FIG. 1 is a perspective view showing the overall appearance of the rotation speed switching device of this creation;
FIG. 2 is a three-dimensional exploded view showing the main component combination relationship of the rotation speed switching device of this creation;
3 is a schematic plan sectional view showing the structure of the rotation speed switching device of the present invention and being switched to a low rotation speed state;
4 is a right side view of FIG. 3;
5 is a plan sectional view taken along the 5-5 direction of FIG. 3;
6 is a plan sectional view taken along the direction 6-6 of FIG. 3;
7 is a schematic plan sectional view showing that the rotation speed switching device of the present invention is switched to a high rotation speed state;
FIG. 8 is a plan sectional view taken along the 8-8 direction of FIG. 7; and FIG. 9 is a plan sectional view taken along the 9-9 direction of FIG.

Claims (6)

A rotation speed switching device for an electric tool includes:
A first planetary gear mechanism, the first planetary gear mechanism includes a plurality of first planetary gears;
A second planetary gear mechanism, the first planetary gear mechanism is movably connected in series in an axial direction, and the second planetary gear mechanism includes a plurality of second planetary gears;
A motor gear connected to a motor, and the motor gear axially meshes the first planetary gear and the second planetary gear; and an output shaft, axially connected to the first planetary gear mechanism,
Wherein, when the first planetary gear mechanism is restricted by external force but the second planetary gear mechanism is not restricted by external force, the motor gear transmits power to the output shaft through the second planetary gear mechanism and the first planetary gear mechanism. A low speed is generated. When the second planetary gear mechanism is limited by external force but the first planetary gear mechanism is not limited by external force, the motor gear transmits power to the output through the second planetary gear mechanism and the first planetary gear mechanism. The shaft to produce high speeds,
It is characterized by:
The first planetary gear mechanism further includes a first internal gear, and an inner diameter and an outer diameter of the first internal gear form a first internal tooth portion and a first external tooth portion, respectively. The first planetary gear meshes, and the first external tooth portion matches at least one first detent element;
The second planetary gear mechanism further includes a second internal gear, and the inner and outer diameters of the second internal gear form a second internal tooth portion and a second external tooth portion, respectively. A second planetary gear meshes, the second external tooth portion matches at least one second detent element; and further includes a knob provided on the periphery of the first planetary gear mechanism and the second planetary gear mechanism, the knob having a detent When the knob is rotated by an angle in a first direction, the actuating structure applies an external force to the first planetary gear mechanism to restrict the first internal gear to be fixed, but the second planetary gear mechanism does not have Limited by external force, the second internal gear can be rotated, so that the motor gear is switched to a low speed mode. When the knob is rotated by an angle in an opposite second direction, the detent structure imparts to the second planet The second internal gear is restricted to be fixed by an external force of the gear mechanism, but the first planetary gear mechanism is not restricted by the external force to allow the first internal gear to rotate, so that the motor gear is switched High speed mode. According to the rotation speed switching device of the electric tool according to item 1 of the scope of patent application, wherein the first internal tooth portion and the second internal tooth portion have different numbers of teeth, respectively. The rotation speed switching device for an electric tool according to item 2 of the patent application scope, further comprising a housing having an inner space, and the first planetary gear mechanism and the second planetary gear mechanism are disposed in the inner space. , The side wall of the shell separates a front section area and a rear section area along the center axis direction, the side wall of the front section area is provided with a plurality of front locking holes along the circumference, and the side wall of the rear section area is provided with a plurality of along the circumference. Rear locking holes, the front locking holes and the rear locking holes being staggered from each other in the circumferential direction of the casing, the first locking element is provided in the front locking hole, and the second locking element is provided in the Inside the rear locking hole. According to the rotation speed switching device of the electric tool according to item 3 of the patent application scope, wherein the detent structure is a switching ring, the side wall of the switching ring separates a front section area and a rear section area along the direction of its central axis. A plurality of front slots are arranged along the circumference of the side wall in the front section, and a plurality of back slots are arranged along the circumference of the side wall in the rear section. The front slot and the back slot are mutually adjacent in the circumferential direction of the switching ring. Staggered by an angle, the switch ring is set at the inner diameter of the knob. When the knob is combined with the casing, the inner diameter of the switch ring is slid to fit the outer diameter of the casing. After the knob is rotated by an angle in the first direction, The front slot hole of the switch ring does not correspond to the position of the front lock hole, so that the side wall of the switch ring pushes the first detent element into the first external tooth portion to fix the first internal gear, but the The rear slot hole of the switching ring corresponds to the position of the rear locking hole, so that the second detent element is not embedded in the second external tooth portion and the second internal gear can be rotated. When the knob is rotated in the second direction After an angle, the cut The front slot hole of the change ring corresponds to the position of the front lock hole, so that the first detent element is not embedded in the first external tooth portion and the first internal gear can be rotated, but the rear slot hole of the switch ring is not Corresponding to the position of the rear locking hole, the side wall of the switching ring pushes the second detent element into the second external tooth portion to fix the second internal gear. According to the rotation speed switching device of the electric tool according to item 4 of the scope of patent application, wherein the first detent element and the second detent element are steel balls, respectively. The rotation speed switching device of an electric tool as described in the scope of application for patent No. 5 wherein,
The first planetary gear mechanism includes a first planetary gear plate, and the first planetary gear plate is rotatably combined with a plurality of the first planetary gears by a plurality of first pinion stub shafts;
The second planetary gear mechanism includes a second planetary gear plate, and the second planetary gear plate is rotatably combined with a plurality of the second planetary gears by a plurality of second pinion stub shafts; and the motor gear is formed in a step form and A first gear tooth portion having a different diameter and a second gear tooth portion, the first gear tooth portion meshes with the second planetary gears, and the second gear tooth portion meshes with the first planetary gears.